Set of key buttons for a handset



FIG. 1 is a front view of a set of key buttons for a handset showing my new design; and,

FIG. 2 is a perspective front view thereof.

The broken line showings of the remainder of the handset are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a set of key buttons for a handset, as shown and described. 